43 resultados para GLOBAL WELL-POSEDNESS
Resumo:
Paleoecology can provide valuable insights into the ecology of species that complement observation and experiment-based assessments of climate impact dynamics. New paleoecological records (e.g., pollen, macrofossils) from the Italian Peninsula suggest a much wider climatic niche of the important European tree species Abies alba (silver fir) than observed in its present spatial range. To explore this discrepancy between current and past distribution of the species, we analyzed climatic data (temperature, precipitation, frost, humidity, sunshine) and vegetation-independent paleoclimatic reconstructions (e.g., lake levels, chironomids) and use global coupled carbon-cycle climate (NCAR CSM1.4) and dynamic vegetation (LandClim) modeling. The combined evidence suggests that during the mid-Holocene (6000 years ago), prior to humanization of vegetation, A. alba formed forests under conditions that exceeded the modern (1961-1990) upper temperature limit of the species by 5-7°C (July means). Annual precipitation during this natural period was comparable to today (>700-800 mm), with drier summers and wetter winters. In the meso-Mediterranean to sub-Mediterranean forests A. alba co-occurred with thermophilous taxa such as Quercus ilex, Q. pubescens, Olea europaea, Phillyrea, Arbutus, Cistus, Tilia, Ulmus, Acer, Hedera helix, Ilex aquifolium, Taxus, and Vitis. Results from the last interglacial (ca. 130 000-115 000 BP), when human impact was negligible, corroborate the Holocene evidence. Thermophilous Mediterranean A. alba stands became extinct during the last 5000 years when land-use pressure and specifically excessive anthropogenic fire and browsing disturbance increased. Our results imply that the ecology of this key European tree species is not yet well understood. On the basis of the reconstructed realized climatic niche of the species, we anticipate that the future geographic range of A. alba may not contract regardless of migration success, even if climate should become significantly warmer than today with summer temperatures increasing by up to 5-7°C, as long as precipitation does not fall below 700-800 mm/yr, and anthropogenic disturbance (e.g., fire, browsing) does not become excessive. Our finding contradicts recent studies that projected range contractions under global-warming scenarios, but did not factor how millennia of human impacts reduced the realized climatic niche of A. alba.
Resumo:
The end of the Last Glacial Maximum (Termination I), roughly 20 thousand years ago (ka), was marked by cooling in the Northern Hemisphere, a weakening of the Asian monsoon, a rise in atmospheric CO2 concentrations and warming over Antarctica. The sequence of events associated with the previous glacial–interglacial transition (Termination II), roughly 136 ka, is less well constrained. Here we present high-resolution records of atmospheric CO2 concentrations and isotopic composition of N2—an atmospheric temperature proxy—from air bubbles in the EPICA Dome C ice core that span Termination II. We find that atmospheric CO2 concentrations and Antarctic temperature started increasing in phase around 136 ka, but in a second phase of Termination II, from 130.5 to 129 ka, the rise in atmospheric CO2 concentrations lagged that of Antarctic temperature unequivocally. We suggest that during this second phase, the intensification of the low-latitude hydrological cycle resulted in the development of a CO2 sink, which counteracted the CO2 outgassing from the Southern Hemisphere oceans over this period.
Resumo:
A recent study relying purely on statistical analysis of relatively short time series suggested substantial re-thinking of the traditional view about causality explaining the detected rising trend of atmospheric CO2 (atmCO2) concentrations. If these results are well-justified then they should surely compel a fundamental scientific shift in paradigms regarding both atmospheric greenhouse warming mechanism and global carbon cycle. However, the presented work suffers from serious logical deficiencies such as, 1) what could be the sink for fossil fuel CO2 emissions, if neither the atmosphere nor the ocean – as suggested by the authors – plays a role? 2) What is the alternative explanation for ocean acidification if the ocean is a net source of CO2 to the atmosphere? Probably the most provocative point of the commented study is that anthropogenic emissions have little influence on atmCO2 concentrations. The authors have obviously ignored the reconstructed and directly measured carbon isotopic trends of atmCO2 (both δ13C, and radiocarbon dilution) and the declining O2/N2 ratio, although these parameters provide solid evidence that fossil fuel combustion is the major source of atmCO2 increase throughout the Industrial Era.
Resumo:
About 500,000 elderly people in Switzerland suffer a fall each year. Thus medical attention and help are essential for these people, who mostly live alone without a caregiver. Only 3% of people aged over 65 in Switzerland use an emergency system. Personal telehealth devices allow patients to receive enough information about the appropriate treatment, as well as followup with their doctors and reports of any emergency, in the absence of any caregiver. This increases their quality of life in a cost-effective fashion. "Limmex"-a new medical emergency watch-was launched in Switzerland in 2011 and has been a great commercial success. In this paper, we give a brief review of this watch technology, along with the results of a survey of 620 users conducted by the Department of Emergency Medicine in Bern.
Resumo:
“Cultural diversity” has become one of the latest buzzwords on the international policymaking scene. It is employed in various contexts – sometimes as a term close to “biological diversity”, at other times as correlated to the “exception culturelle” and most often, as a generic concept that is mobilised to counter the perceived negative effects of economic globalisation. While no one has yet provided a precise definition of what cultural diversity is, what we can observe is the emergence of the notion of cultural diversity as incorporating a distinct set of policy objectives and choices at the global level. These decisions are not confined, as one might have expected, to cultural policymaking, but rather spill over to multiple governance domains because of the complex linkages inherent to the simultaneous pursuit of economic and other societal goals that cultural diversity encompasses and has effects on. Accounting for these intricate interdependencies, the present article clarifies the origins of the concept of cultural diversity as understood in global law and traces its evolution over time. Observing the dynamics of the concept and the surrounding political and legal developments, the article explores its justification and overall impact on the global legal regime, as well as its discrete effects on different domains of policymaking, such as media, intellectual property and culture. While the analysis is legal in essence, the article is meant to speak also to a broader transdisciplinary public. The article is part of the speacial issue on ethnic diversity and cultural pluralism, which is available under the creative commons licence: http://www.mdpi.com/journal/diversity/special_issues/ethnic-diversity/.
Resumo:
The paper seeks a re-conceptualization of the global digital divide debate. It critically explores the predominant notion, its evolution and measurement, as well as the policies that have been advanced to bridge the digital divide. Acknowledging the complexity of this inequality, the paper aims at analyzing the disparities beyond the connectivity and the skills barriers. Without understating the first two digital divides, it is argued that as the Internet becomes more sophisticated and more integrated into economic, social and cultural processes, a ‘third’ generation of divides becomes critical. These divides are drawn not at the entry to the net but within the net itself, and limit access to content. The increasing barriers to content, although of diverse nature, all relate to some governance characteristics inherent in cyberspace, such as global spillover of local decisions, regulation through code or proliferation of self- and co-regulatory models. It is maintained that as the practice of intervention intensifies in cyberspace, multiple and far-reaching points of control outside formal legal institutions are created, which threaten the availability of public goods and make the pursuit of public objectives difficult. This is an aspect that is rarely addressed in the global digital divide discussions, even in comprehensive analysis and political initiatives such as the World Summit on the Information Society. Yet, the conceptualization of the digital divide as impeded access to content may be key in terms of ensuring real participation and catering for the long-term implications of digital technologies.
Resumo:
The article seeks a re-conceptualization of the global digital divide debate. It critically explores the predominant notion, its evolution and measurement, as well as the policies that have been advanced to bridge the digital divide. Acknowledging the complexity of this inequality, the article aims at analyzing the disparities beyond the connectivity and skills barriers. Without understating the first two digital divides, it is argued that as the Internet becomes more sophisticated and more integrated into economic, social, and cultural processes, a “third” generation of divides becomes critical. These divides are drawn not at the entry to the net but within the net itself, and limit access to content. The increasing barriers to content, though of a diverse nature, all relate to some governance characteristics inherent in cyberspace, such as global spillover of local decisions, regulation through code, and proliferation of self- and co-regulatory models. It is maintained that as the practice of intervention intensifies in cyberspace, multiple and far-reaching points of control outside formal legal institutions are created, threatening the availability of public goods and making the pursuit of public objectives difficult. This is an aspect that is rarely addressed in the global digital divide discussions, even in comprehensive analyses and political initiatives such as the World Summit on the Information Society. Yet, the conceptualization of the digital divide as impeded access to content may be key in terms of ensuring real participation and catering for the long-term implications of digital technologies.
Resumo:
The intensified flows of goods, services, peoples and ideas across borders intrinsic to globalization have had numerous and multi-faceted effects. Those affecting culture have been perhaps the most controversial, as it is more often than not difficult to identify the spill-overs across economic and non-economic areas and across borders, as it is equally hard to qualify the effects of these spill-overs as positive or negative. The debate also tends to be politically and even emotionally charged, which has so far not proven advantageous to establishing a genuine dialogue, nor to finding solutions. This contention and the divergent interests of major players in the international community have been reflected in the institutions and rules of global law. It is the objective of this chapter to explore this institutional architecture, in particular its main (and opposing) constituent fora of the World Trade Organization (WTO) and the United Nations Educational Social and Cultural Organization (UNESCO). The chapter traces the evolution of these institutions and their interaction over time, as well as the underlying objectives, demands and strategies of the key proponents in the trade versus culture discourse, which ultimately shaped the existent law and policy. The chapter concludes with an appraisal of the present state of affairs situating the discussion into the contemporary global governance landscape.
Resumo:
Currently, dramatic changes are happening in the IS development industry. The incumbent system developers (hubs) are embracing partnerships with less well established companies (spokes), acting in specific niches. This paper seeks to establish a better understanding of the motives for this strategy. Relying on existing work on strategic alliance formation, it is argued that partnering is particularly attractive, if these small companies possess certain capabilities that are difficult to obtain through other arrangements than partnering. Again drawing on the literature, three categories of capabilities are identified: the capability to innovate within their niche, the capability to provide a specific functionality that can be integrated with the incumbents’ systems, and the capability to address novel markets. These factors are analyzed through a case study. The case represents a market leader in the global IS development industry, which fosters a network of smaller partner firms. The study reveals that temporal dynamics between the identified factors are playing a dominant role in these networks. A cyclical partnership model is developed that attempts to explain the life cycle of a partnership within such a network.
Resumo:
We estimate the effects of climatic changes, as predicted by six climate models, on lake surface temperatures on a global scale, using the lake surface equilibrium temperature as a proxy. We evaluate interactions between different forcing variables, the sensitivity of lake surface temperatures to these variables, as well as differences between climate zones. Lake surface equilibrium temperatures are predicted to increase by 70 to 85 % of the increase in air temperatures. On average, air temperature is the main driver for changes in lake surface temperatures, and its effect is reduced by ~10 % by changes in other meteorological variables. However, the contribution of these other variables to the variance is ~40 % of that of air temperature, and their effects can be important at specific locations. The warming increases the importance of longwave radiation and evaporation for the lake surface heat balance compared to shortwave radiation and convective heat fluxes. We discuss the consequences of our findings for the design and evaluation of different types of studies on climate change effects on lakes.
Resumo:
The surrounding capsule of Streptococcus pneumoniae has been identified as a major virulence factor and is targeted by pneumococcal conjugate vaccines (PCV). However, nonencapsulated Streptococcus pneumoniae (Non-Ec-Sp) have also been isolated globally, mainly in carriage studies. It is unknown if Non-Ec-Sp evolve sporadically, if they have high antibiotic non-susceptiblity rates and a unique, specific gene content. Here, whole genome sequencing of 131 Non-Ec-Sp isolates sourced from 17 different locations around the world was performed. Results revealed a deep-branching classic lineage that is distinct from multiple sporadic lineages. The sporadic lineages clustered with a previously sequenced, global collection of encapsulated S. pneumoniae (Ec-Sp) isolates while the classic lineage is comprised mainly of the frequently identified multi-locus sequences types ST344 (n=39) and ST448 (n=40). All ST344 and nine ST448 isolates had high non-susceptiblity rates to β-lactams and other antimicrobials. Analysis of the accessory genome reveals that the classic Non-Ec-Sp contained an increased number of mobile elements, than Ec-Sp and sporadic Non-Ec-Sp. Performing adherence assays to human epithelial cells for selected classic and sporadic Non-Ec-Sp revealed that the presence of a integrative conjugative element (ICE) results in increased adherence to human epithelial cells (P=0.005). In contrast, sporadic Non-Ec-Sp lacking the ICE had greater growth in vitro possibly resulting in improved fitness. In conclusion, Non-Ec-Sp isolates from the classic lineage have evolved separately. They have spread globally, are well adapted to nasopharyngeal carriage and are able to coexist with Ec-Sp. Due to continued use of pneumococcal conjugate vaccines, Non-Ec-Sp may become more prevalent.
Resumo:
Taking up the thesis of Dipesh Chakrabarty (2009) that human history (including cultural history) on the one hand and natural history on the other must be brought into conversation more than has been done so in the past, this presentation will focus more closely on the significance and the impact of global climatic conditions and pests on the negotiations that Australian Prime Minister William Morris Hughes carried on with the British government between March and November 1916. Whereas Australia had been able to sell most of its produce in 1914 and 1915 the situation looked more serious in 1916, not least due to the growing shortage in shipping. It was therefore imperative for the Australian government to find a way to solve this problem, not least because it wanted to keep up its own war effort at the pace it had been going so far. In this context intentions to make or press ahead with a contribution to a war perceived to be more total those of the past interacted with natural phenomena such as the declining harvest in many parts of the world in 1916 as a consequence of climatic conditions as well as pests in many parts of the world.
Resumo:
Potential desiccation polygons (PDPs) are polygonal surface patterns that are a common feature in Noachian-to-Hesperian-aged phyllosilicate- and chloride-bearing terrains and have been observed with size scales that range from cm-wide (by current rovers) to 10s of meters-wide. The global distribution of PDPs shows that they share certain traits in terms of morphology and geologic setting that can aid identification and distinction from fracturing patterns caused by other processes. They are mostly associated with sedimentary deposits that display spectral evidence for the presence of Fe/Mg smectites, Al-rich smectites or less commonly kaolinites, carbonates, and sulfates. In addition, PDPs may indicate paleolacustrine environments, which are of high interest for planetary exploration, and their presence implies that the fractured units are rich in smectite minerals that may have been deposited in a standing body of water. A collective synthesis with new data, particularly from the HiRISE camera suggests that desiccation cracks may be more common on the surface of Mars than previously thought. A review of terrestrial research on desiccation processes with emphasis on the theoretical background, field studies, and modeling constraints is presented here as well and shown to be consistent with and relevant to certain polygonal patterns on Mars.
Resumo:
While most events related to the International Year of Deserts and Desertification 2006 took mainly a problem-oriented perspective and approach, the Bern Symposium held in May 2006 tried to adopt a more positive attitude by attempting to take stock of experience as well as best and worst practices in the past, both in development practice and in research. Through this deliberate focus on potentials, positive experiences, solutions and pathways, predominant passive and reactive attitudes and hopelessness might be better overcome. The Symposium was organized by CDE, NCCR North-South and Forum SLM.
Resumo:
The main aim of the methodology presented in this paper is to provide a framework for a participatory process for the appraisal and selection of options to mitigate desertification and land degradation. This methodology is being developed within the EU project DESIRE (www.desire-project.eu/) in collaboration with WOCAT (www.wocat.org). It is used to select promising conservation strategies for test-implementation in each of the 16 degradation and desertification hotspot sites in the Mediterranean and around the world. The methodology consists of three main parts: In a first step, prevention and mitigation strategies already applied at the respective DESIRE study site are identified and listed during a workshop with representatives of different stakeholders groups (land users, policy makers, researchers). The participatory and process-oriented approach initiates a mutual learning process among the different stakeholders by sharing knowledge and jointly reflecting on current problems and solutions related to land degradation and desertification. In the second step these identified, locally applied solutions (technologies and approaches) are assessed with the help of the WOCAT methodology. Comprehensive questionnaires and a database system have been developed to document and evaluate all relevant aspects of technical measures as well as implementation approaches by teams of researchers and specialists, together with land users. This research process ensures systematic assessing and piecing together of local information, together with specific details about the environmental and socio-economic setting. The third part consists of another stakeholder workshop where promising strategies for sustainable land management in the given context are selected, based on the best practices database of WOCAT, including the evaluated locally applied strategies at the DESIRE sites. These promising strategies will be assessed with the help of a selection and decision support tool and adapted for test-implementation at the study site.